class Solution {
public:
    int maxProfit(vector<int>& prices) {
        int ret = 0, sz = prices.size();
        for (int i = 1; i < sz; i++)
        {
            if(prices[i] > prices[i - 1])
                ret += prices[i] - prices[i - 1];
        }
        return ret;
    }
};